Accelerometer Autoprom hmmmm
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Accelerometer Autoprom hmmmm
Well I know there is analog inputs in the autoprom, and thinking this may be a valuable tool. Anyone out there ever gone this route? http://www.dimensionengineering.com/DE-ACCM3D.htm
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Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
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Re: Accelerometer Autoprom hmmmm
Hmmmm is right.
Very neat idea.
Very neat idea.
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Re: Accelerometer Autoprom hmmmm
That set up is nice with a decent price. I put together and have a 2-axis accelerometer in the '67. And just the sensor was close to $24. They may have come down in price, don't know.
Note that they are tricky to use. Any slope, up/down/sideways will show up as a force. So to interpret the data correctly need to take into account these variables. Analog Devices also makes gyro sensors that would really be the cat's meow.
As for the data from the g-sensor, I haven't done much with it. The cornering g's is interesting just to see what it is. But body lean affects the reading. Along with the camber of the road.
Same when accelerating, front end rise will show as additional acceleration. Although with the 3D sensor should/may be able to post process using the Z axis to compensate.
What I figured would be the best use for engine tuning using the g reading would be on the strip. You would be able to see the acceleration curve through the engines power band. Could adjust timing at a particular RPM and re-run. Then look at the data to see if that area picked up, stayed the same, or dropped off.
Using the same area of road (strip) would also take the slope of the road variable out. As it would remain the same. The readings would then be relative to each other.
Note that you can also graph the MPH to derive the rate of acceleration. Just need to watch for tire spin which would skew those results.
RBob.
Note that they are tricky to use. Any slope, up/down/sideways will show up as a force. So to interpret the data correctly need to take into account these variables. Analog Devices also makes gyro sensors that would really be the cat's meow.
As for the data from the g-sensor, I haven't done much with it. The cornering g's is interesting just to see what it is. But body lean affects the reading. Along with the camber of the road.
Same when accelerating, front end rise will show as additional acceleration. Although with the 3D sensor should/may be able to post process using the Z axis to compensate.
What I figured would be the best use for engine tuning using the g reading would be on the strip. You would be able to see the acceleration curve through the engines power band. Could adjust timing at a particular RPM and re-run. Then look at the data to see if that area picked up, stayed the same, or dropped off.
Using the same area of road (strip) would also take the slope of the road variable out. As it would remain the same. The readings would then be relative to each other.
Note that you can also graph the MPH to derive the rate of acceleration. Just need to watch for tire spin which would skew those results.
RBob.
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Re: Accelerometer Autoprom hmmmm
That set up is nice with a decent price. I put together and have a 2-axis accelerometer in the '67. And just the sensor was close to $24. They may have come down in price, don't know.
Note that they are tricky to use. Any slope, up/down/sideways will show up as a force. So to interpret the data correctly need to take into account these variables. Analog Devices also makes gyro sensors that would really be the cat's meow.
As for the data from the g-sensor, I haven't done much with it. The cornering g's is interesting just to see what it is. But body lean affects the reading. Along with the camber of the road.
Same when accelerating, front end rise will show as additional acceleration. Although with the 3D sensor should/may be able to post process using the Z axis to compensate.
What I figured would be the best use for engine tuning using the g reading would be on the strip. You would be able to see the acceleration curve through the engines power band. Could adjust timing at a particular RPM and re-run. Then look at the data to see if that area picked up, stayed the same, or dropped off.
Using the same area of road (strip) would also take the slope of the road variable out. As it would remain the same. The readings would then be relative to each other.
Note that you can also graph the MPH to derive the rate of acceleration. Just need to watch for tire spin which would skew those results.
RBob.
Note that they are tricky to use. Any slope, up/down/sideways will show up as a force. So to interpret the data correctly need to take into account these variables. Analog Devices also makes gyro sensors that would really be the cat's meow.
As for the data from the g-sensor, I haven't done much with it. The cornering g's is interesting just to see what it is. But body lean affects the reading. Along with the camber of the road.
Same when accelerating, front end rise will show as additional acceleration. Although with the 3D sensor should/may be able to post process using the Z axis to compensate.
What I figured would be the best use for engine tuning using the g reading would be on the strip. You would be able to see the acceleration curve through the engines power band. Could adjust timing at a particular RPM and re-run. Then look at the data to see if that area picked up, stayed the same, or dropped off.
Using the same area of road (strip) would also take the slope of the road variable out. As it would remain the same. The readings would then be relative to each other.
Note that you can also graph the MPH to derive the rate of acceleration. Just need to watch for tire spin which would skew those results.
RBob.
The only thing holding me back now is an accurate way to quantify the performance. I have been calculating the power based on my delta speed over time, but unfortunately the output rate of the ecm is not fast enough to be used as a repeatble and reliable gage. I should be able to make a good model with a precise measurement system, so as long as my tilt factor is relatively the same it should be somewhat precise. Accuracy isn't a huge concern as the statistical approach that I will be using is based on precision.
Another thing I will have to do is ensure that several factors remain constant- atmospheric conditions, weight in car, temperature etc. I may see the data change over time because of oil temps slowly rising etc.
I have also seen that they make accelerometers on ebay specifically for automotive applications. I am opting not to go this route as I would prefer to not have to worry about lining up the time stamps of my data. However, there are 3 axis and look like they accomadate for body roll, hills, etc.
Rbob, depending on the accelerometer that you have now you can change the orientation on some so that it can be x and z. Then when you output the data you could compensate for the body roll front to back. I will have to check out the gyro sensors you mentioned above, I have never heard of them.
I am going to go ahead and purchase one of these and will let everyone know how my gage r+r turns out. If I get a good gauge I have plenty of ideas up my sleeve that I will be sure to share later.
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Re: Accelerometer Autoprom hmmmm
The 2 axis sensor could be placed in the X and Z axis. Same if I wanted to measure the Y axis and Z axis. No problem with changing the axis. It is just that it will offset the center of the Z axis by the force of gravity. And change the available range of the sensor.
Here is a link to the Analog Devices inertial sensors. This includes the accelerometers and gyroscope devices.
http://www.analog.com/en/sensors/ine...cts/index.html
Some of the older sensors have come down in price. But they have also added less expensive devices since that time. Note that there are differences in accuracy & noise between the older & newer devices.
RBob.
Here is a link to the Analog Devices inertial sensors. This includes the accelerometers and gyroscope devices.
http://www.analog.com/en/sensors/ine...cts/index.html
Some of the older sensors have come down in price. But they have also added less expensive devices since that time. Note that there are differences in accuracy & noise between the older & newer devices.
RBob.
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